In many industries, including, for example, the food and beverage processing industry, containers and other articles are transported from one location to another location by conveyors such as belt conveyors. In many such conveyor systems, a lubricating composition is used on the conveyor. One of the reasons that a lubricating composition is used is to facilitate movement and reduce the damage to the container resulting from mechanical impact between the containers and the rubbing action among the containers and between the containers and the belt. For example, occasionally in such systems, the containers are stopped on the conveyor due to a back up on the conveyor. While the containers are stopped, the belt is often still moved continuously. To facilitate the smooth transportation of the containers, a lubricating composition can be applied onto the surface of the conveyor belt and/or the containers.
There can be numerous challenges in providing lubricating composition for use on conveyors. One example of a potential challenge deals with the desire for a lubricant that can be used on a broad variety of materials. For example, conveyors can be made of plastic, metal, or other materials, and the articles and containers being transported can likewise be made of a broad variety of materials, for example plastic, metal, glass, cardboard, paper, and the like. It is desirable that a lubricant be useful in more than just one application with one type of container and/or conveyor material.
Additionally, there is a desire for lubricants for conveyors that provide lubricity while showing a reduced amount of detrimental effects on the conveyors or on the articles and/or containers being conveyed. For instance, in some applications, the containers, or portions of the conveyors are made of thermoplastic materials. In such applications, it is desirable that the lubricating composition used be thermoplastic compatible. For example, in some applications that use fatty acids to make fatty acid soaps for use in lubricants, a high level of alkali neutralizing agent is required in order to neutralize the fatty acid in an aqueous composition. The use of higher amounts of alkali neutralizing agent, such as hydroxides and certain amines, in fatty acid soap containing lubricants, significantly increases the alkalinity of the lubricants. The increased level of alkalinity contributes to and promotes stress cracking in some thermoplastic containers, for example PET containers. The increased level of alkalinity can also contribute to and promote removal of some printed materials, such as printed codes on containers.
The prior art offers a number of different compositions and methods for lubricating conveyor systems. Each of these different compositions and methods can have certain advantages and disadvantages. There is an ongoing need to provide alternative compositions and methods for lubricating conveyor systems.